Combination of all-trans-retinoic acid and gemtuzumab ozogamicin in an elderly patient with acute promyelocytic leukemia and severe cardiac failure

All-trans-retinoic acid (ATRA) combined with anthracyclines is currently the standard treatment for acute promyelocytic leukemia (APL). In elderly patients the presence of comorbidities, such as cardiomyopathy or different organ failures, often represents an absolute contraindication to standard chemotherapy. In this particular setting of patients, alternative front-line approaches are needed. Here we report the use of gemtuzumab ozogamicin as consolidation therapy in a 68-year-old patient not eligible for standard dose anthracycline due to severe cardiac failure and chronic anticoagulant therapy, affected by low-risk APL. Induction therapy was started with ATRA alone, at a dose of 45 mg/m2 for 80 days. The patient obtained a complete hematological and molecular remission. At day +170 the patient was treated with 6 mg/m2 gemtuzumab ozogamicin monthly for two months (2 total doses) as a consolidation therapy and then started a maintenance program with ATRA 45 mg/m2 for 15 days every three months, for a total time of two years. No adverse events were observed in every phase of treatment and the patient is still in complete continuous hematological and molecular remission 29 months from diagnosis. This approach represents an intriguing therapeutic option to be investigated in randomized studies in low- and intermediate-risk elderly patients (older than 65 years), aiming to minimize or to eliminate standard chemotherapy in advantage of new non-conventional agents, including ATO.     

Predictive factors of all-trans-retinoic acid related complications during induction therapy for acute promyelocytic leukemia

Abstract

Background: The combination of all-trans-retinoic acid (ATRA) and chemotherapy has made acute promyelocytic leukemia (APL) a highly curable leukemia. However, several complications are reported with this treatment the most serious and life threatening being Retinoic Acid Syndrome (RAS). We aimed at identifying factors that could predict complications caused by ATRA during induction treatment of APL.

Patients: Forty-two patients with confirmed APL (by t(15;17) and/or PML/RARA) treated at our institution (University hospital of Tunis) between January 1998 and June 2006 using two consecutive protocols: European APL93 trial (24 patients) until February 2004 and Spanish PETHEMA LPA99 trial (18 patients) more recently. Induction regimen consisted of ATRA 45 mg/m²/d until CR combined to DNR 60 mg/m²/d×3+Cytarabine 200 mg/m²/d×7 (APL93) and Idarubicin 12 mg/m² d2, 4, 6, 8 (LPA99). Prednisone (0·5 mg/kg d1–d15) was added if WBC >10×10⁹/L to prevent RAS in LPA 99.

Results: Median age was 36 yr (7–64 yr), M/F=16/26 (0·61), median WBC was 2·4×10⁹/L (range 0·6–100×10⁹/L). WBC >10×10⁹/L was noted in 14 patients (33%). Additional cytogenetic abnormalities were seen in 12/42 (28%). Median body mass index (BMI=weight/height²:N 20–25) was 24 kg/m² (range 16–40 kg/m²), BMI >30 was noted in nine patients (8F and 1M). Thirty-three patients achieved CR (78·57%):18/24 (75%) in APL93 versus 15/18 (83%) in LPA99. Nine patients (21·42%) had early death. Causes of early death were: RAS (6) and CNS hemorrhage (3). Complications due to ATRA were: RAS (10), Scrotal ulcerations (3), Sweet syndrome (2), Perineal ulcerations (1), and Pseudotumor cerebri (1). Prognostic factors for complications of ATRA (Fisher exact test) were: BMI >35 (p=0·055), induction treatment without cytarabine (LPA99 trial) (p=0·047), whereas age (p=0·74), gender (p=0·51), initial WBC (p=0·47), and additional cytogenetic abnormalities (p=0·83) were not predictive. Retinoic Acid Syndrome was more reported in patients with initial WBC >10×10⁹/L (p=0·08).

Conclusion: We found high BMI (>35) in female and treatment without Cytarabine to increase the risk of developing complications with ATRA.     

Molecular evaluation of response to all-trans-retinoic acid therapy in patients with acute promyelocytic leukemia.

The advent of retinoic acid (RA) in the treatment of acute promyelocytic leukemia (APL) has led to a high frequency of short-lasting complete remissions (CR). We studied the response to RA by molecularly analyzing the RA receptor alpha (RAR alpha) locus, which has recently been shown to be rearranged in all APLs. Southern blot analysis demonstrated that the RAR alpha rearrangements persisted in the APL samples containing maturing myeloid cells 2 to 3 weeks after the start of RA treatment, but disappeared after 5 to 8 weeks, when the patients achieved CR. Our investigations provide clear evidence that CR occurs at molecular level and that there is reconstitution of an apparently normal, nonclonal hematopoiesis. Further, it shows that RA acts by triggering differentiation rather than by exerting a cytotoxic effect on the leukemic clone.     

Activity of all-trans-retinoic acid in a case of central nervous system extramedullary relapse of acute promyelocytic leukemia

We describe a patient with an acute promyelocytic leukemia (APL) previously treated with two courses of cytarabin, idarubicin and all-trans retinoic acid (ATRA), who presented a medullary and meningeal relapse after 8 months of complete remission. A diagnosis of central nervous system (CNS) involvement was based on the appearance of APL blasts in the cerebrospinal fluid (CSF); magnetic resonance (MR) imaging was negative. The neurological symptoms were not evident at the time of recognition of the medullary recurrence, but appeared a few days later, when the patient had already received a reinduction treatment. When the CSF was first examined, showing atypical promyelocytes, there was no excess of blasts on bone-marrow examination. The patient was treated with ATRA and intrathecal administrations of cytoxic drugs, achieving a complete long-lasting CNS remission. The appearance of mature myeloid cells in the CSF during this treatment suggested a possible differentiating effect of ATRA towards extramedullary relapse.     

Effect of additional chromosomal abnormalities in acute promyelocytic leukemia treated with all-trans-retinoic acid: a report of 17 patients

Seventeen cases of acute promyelocytic leukemia (APL) treated with all-trans-retinoic acid (ATRA) and combination chemotherapy at Tokyo Metropolitan Komagome Hospital between 1992 and 1999 were reviewed, and divided into 2 karyotype-based cytogenetic groups. One group comprised 7 patients with either the typical t(15;17) alone or a normal karyotype, and the other group comprised 10 patients with additional karyotypic abnormalities. No patient had received prior chemotherapy or irradiation, and no cases were complicated by a history of myelodysplastic syndrome before the diagnosis of APL. There were no significant differences in clinical characteristics at disease presentation. Complete remission was achieved in all 17 patients and karyotypes of bone marrow cells normalized in all cases. No differences were found in relapse rate, overall survival, or disease-free survival between the 2 groups. The analysis did not reveal any significant effect of additional chromosomal abnormalities on the prognosis of APL patients undergoing treatment with ATRA. However, a small number of patients were assessed in this study, and further cumulative studies are needed.     

Loss of blast cell procoagulant activity and improvement of hemostatic variables in patients with acute promyelocytic leukemia administered all-trans-retinoic acid

All-trans-retinoic acid (ATRA) induces complete remission (CR) in up to 90% of acute promyelocytic leukemia (APL) patients with rapid amelioration of the bleeding syndrome. Previous studies indicate that ATRA treatment in vitro of the APL NB4 cell line can affect their procoagulant activity (PCA). To assess whether ATRA has this effect also in vivo, we prospectively studied the PCA of bone marrow blasts from APL patients on therapy with ATRA alone or associated with chemotherapy. Samples were obtained before, during, and after ATRA. To characterize the coagulopathy, we measured a series of plasma hemostatic variables before and during the first two weeks of therapy, as follows: (1) markers of hypercoagulability; (2) natural anticoagulants; (3) fibrinolysis proteins; and (4) elastase. The results by enzymatic and immunologic methods show that both total (tissue factor-like) and factor VII-independent (cancer procoagulant- like) blast cell PCAs, present before therapy, were reduced during (69% and 65% decrement, respectively) and virtually undetectable after ATRA. The plasma hemostatic assessment of patients before treatment was elevated hypercoagulability markers, low mean protein C, normal fibrinolysis proteins, and increased elastase. After starting ATRA, hypercoagulability markers were reduced within 4 to 8 days, protein C augmented, the overall fibrinolytic balance was unmodified, and elastase remained elevated. These results were not different either with or without chemotherapy and are consistent with the clinical findings of rapid improvement of the coagulopathy.     

Treatment of refractory undifferentiated acute myelogenous leukemia with all-trans-retinoic acid

A patient is described with undifferentiated acute myeloblastic leukemia refractory to two courses of daunorubicin and cytosine arabinoside. Because some the myeloblasts developed morphologic features of promyelocytes, the patient was treated with all-trans-retinoic acid (ATRA) in an attempt to promote maturation. Cytogenetic studies and sensitive molecular analysis did not reveal any abnormality classically associated with acute promyelocytic leukemia. Serial bone marrow biopsies demonstrated myeloid maturation, and the patient uneventfully went into a sustained complete remission. A review of the literature confirms this to be an apparently hitherto undescribed response to ATRA that may have therapeutic implications in similar patients. © 1994 Wiley-Liss, Inc.     

Enhanced migration of the acute promyelocytic leukemia cell line NB4 under in vitro conditions during short-term all-trans-retinoic acid treatment

All-trans-retinoic acid (RA) is a potent differentiating agent that is very effective in the treatment of patients with acute promyelocytic leukemia (APL). Since clinical response can be accompanied by extramedullary manifestations, we have investigated the influence of RA on cell adhesion to and migration through reconstituted basement membranes (Matrigel) in the APL cell line NB4. No apparent cellular differentiation was observed during a 24-h incubation with 1 μM RA, as indicated by the nitroblue tetrazolium reduction test. However, exposure to RA significantly enhanced NB4 cell adhesion to Matrigel and consecutive migration through Matrigel barriers in a dose-dependent manner. Several integrin molecules potentially involved in this process, i.e., CD29, CD18, CD11a, CD11b and CD11c, were therefore studied by fluorescence-activated cell sorting analysis. The expression of the β subunit of the β2 integrins (CD18), but not that of β1 integrins (CD29), was increased during 24-h RA treatment. Among the β2 integrins, the expression of LFA-1 (CD11a) and of Mac-1 (CD11b), but not of p150,95 (CD11c), was induced by RA. When monoclonal antibodies that specifically block the interaction of these integrins with their ligands were used, we observed that CD29 is only involved in adhesion and CD11b only in migration, whereas CD11a participates in both processes. NB4 cells constitutively secreted the matrix metalloproteinases MMP-9 and MMP-2, which are known to promote cellular invasion processes by degradation of the extracellular matrix. RA treatment had no influence on the quantity of secreted MMP-9 or MMP-2 in these cells as determined by zymography. Addition of Batimastat (BB-94), a synthetic inhibitor of matrix metalloproteinases, blocked RA-induced cell migration without affecting cellular adhesion to Matrigel. These findings indicate that adhesion molecules as well as matrix metalloproteinases are involved in RA-stimulated migration of NB4 cells through Matrigel, possibly providing some explanation of tissue infiltration by leukemic cells as observed during treatment of APL patients with RA. Received: 27 May 1999 / Accepted: 27 July 1999     

Risk-adapted treatment of acute promyelocytic leukemia with all-trans-retinoic acid and anthracycline monochemotherapy: a multicenter study by the PETHEMA group

All-trans-retinoic acid (ATRA) increases the efficacy of chemotherapy when used for induction and maintenance treatment of acute promyelocytic leukemia (APL), but its role in consolidation is unknown. Since November 1996, 426 patients with newly diagnosed APL have received induction therapy with ATRA and idarubicin. Before November 1999 (LPA96 study), consolidation therapy consisted of 3 courses of anthracycline monochemotherapy. After November 1999 (LPA99 study), patients with intermediate and high risks of relapse received consolidation therapy with ATRA and increased doses of anthracyclines. Of the 384 patients who achieved complete remission (90%), 382 proceeded to consolidation therapy. Seven patients died in remission (1.8%). The 3-year cumulative incidence of relapse for patients in the LPA96 and LPA99 studies was 17.2% and 7.5%, respectively (P =.008). Patients treated with ATRA in consolidation therapy showed an overall reduction in the relapse rate from 20.1% to 8.7% (P =.004). In intermediate-risk patients the rate decreased from 14.0% to 2.5% (P =.006). This improved antileukemic efficacy also translated into significantly better disease-free and overall survival. A risk-adapted strategy combining anthracycline monochemotherapy and ATRA for induction and consolidation therapy of newly diagnosed APL results in improved antileukemic efficacy and a high degree of compliance.     

Retinoic acid as antileukemic therapy in a patient with acute promyelocytic leukemia and Aspergillus pneumonia

A patient with acute promyelocytic leukemia (APL) and laboratory evidence of fibrinolysis who could not be treated with aggressive cytostatic regimens because of Aspergillus pneumonia was treated with cis-retinoic acid (RA), a substance that can induce differentiation and maturation of APL cells. After seven weeks of daily oral treatment, he went into complete remission, and signs of coagulopathy disappeared. Meanwhile, the Aspergillus pneumonia could be treated adequately. Based on the experience in this single patient, RA deserves further evaluation in the treatment of APL.     

Central nervous system relapse with multiple brain masses in an acute promyelocytic leukemia patient treated with all-trans retinoic acid

A 22-year-old woman with fever and bleeding tendency was given a diagnosis of acute promyelocytic leukemia (APL) on the basis of laboratory findings including a WBC count of 106 x 10(3)/microliter (90% blasts) and a platelet count of 1.6 x 10(4)/microliter. Induction therapy was started with all-trans retinoic acid (ATRA) and cytotoxic chemotherapy. After the patient achieved complete remission, ATRA was discontinued and consolidation chemotherapy was started. However, 4 months after onset, leukemic blasts were detected in cerebrospinal fluid. Temporal central nervous system remission was induced by intrathecal chemotherapy only. However, 2 months later, multiple focal mass lesions had developed in the brain. ATRA (45 mg/m2) was restarted together with multiple intrathecal injections of anticancer drugs, and a third remission was achieved. It is conceivable that the incorporation of ATRA in induction chemotherapy is related to the development of this rather rare complication of APL. The outcome in this case suggested orally administered ATRA may be effective in treating brain metastasis of APL.     

Adaptive immunity cooperates with liposomal all-trans-retinoic acid (ATRA) to facilitate long-term molecular remissions in mice with acute promyelocytic leukemia

We previously developed a murine model of acute promyelocytic leukemia (APL) by using human cathepsin G gene regulatory elements to direct the expression of promyelocytic leukemia (PML)/retinoic acid receptor alpha (RAR alpha) and RAR alpha/PML fusion cDNAs to the early myeloid compartment of transgenic mice. To study the efficacy of noncytotoxic therapy in this animal model, cohorts of naive immunocompetent mice were inoculated with primary murine APL cells from a frozen tumor bank. Arsenic trioxide and liposomally encapsulated all-trans-retinoic acid (Lipo ATRA), alone or in combination, were administered for 21 days by i.p. injection using doses that yielded plasma levels similar to those observed in human APL patients treated with these agents. Lipo ATRA was highly effective in inducing durable molecular remissions in immunocompetent mice [C57BL/6 x C3H F(1) (B6C3HF1)]; arsenic therapy was much less effective, and did not clearly synergize with Lipo ATRA to increase the remission rate in immunocompetent mice. The survival of Lipo ATRA-treated severe combined immunodeficient (SCID) animals (lacking functional T and B cells) was inferior to that of immunocompetent B6C3HF1 recipients (40% vs. 88% survival at 1 y, P < 0.001). These data suggest that adaptive immunity cooperates with pharmacologic therapy to induce or maintain remissions in murine APL. It also implies that immunosuppressive anti-leukemia therapies could paradoxically blunt effective anti-leukemia immune responses that are important for clearing small numbers of residual tumor cells after chemotherapy-mediated cytoreduction.